by Lay Leng TAN
anotechnology, a term that used to evoke strong emotion and enthusiasm in researchers and venture capitalists, seems to have fallen on hard times. Not only has the field failed to deliver eagerly anticipated returns, even initial supporters are beginning to feel disillusioned with the seeming lack of progress. Funding has become harder to secure, further slowing down its development. No company with a nano focus has yet gone public in the United States, partly owing to the negative perceptions surrounding the domain.
The ironical reversal of fortune is not lost on K Eric Drexler, the man sometimes accredited as the "father" of nanotechnology. In 1986, Drexler wrote Engines of Creation, which outlined the prospects for advanced molecular-manufacturing technology and introduced the term "molecular nanotechnology" in response to Richard Feynman's famous statement "There is plenty of room at the bottom." That same year he founded Foresight Nanotech Institute, a non-profit think tank and public-interest institute that educates people about nanotechnology's benefits and risks.
Drexler admits that the name creates confusion that now hinders the progress of the field. The initial public enthusiasm dampened with the non-materialisation of lofty idealised scenarios painted by over-optimistic proponents. "I agree with many people who say that the term 'nanotechnology' has become so broad that it is almost meaningless.... It can be applied to almost anything with features less than a hundred nanometres in size, but this includes technologies more than 100 years old such as organic synthesis, Indian ink, and thin-film coatings.
"I think that some people have become disillusioned because of their mental picture of nanotechnology -- in the late 1980s the term conjured up images of tiny machines that built things with atomic precision -- which gave rise to much of the early excitement." Unfortunately, nanoparticles, nanofibres, or coatings cannot meet all of the expectations arising from that technology development scenario, Drexler points out. "There is a mismatch between the older meaning of the term and the public's expectations. Nanotechnology research today is advancing an exciting frontier of science and technology, but we are just beginning to learn how to build molecular machines. Many areas can contribute."
This advocate of nanotechnology recommends that sceptics pay no attention to the nanotechnology label, which refers to a size from 1 to 100nm. He poses the question: if technology in the range 1 to 100cm were dubbed centotechnology, would it then become any less useful?
Drexler is now the chief technical advisor at NanoRex, a US molecular engineering software company. NanoRex's first product, nanoEngineer-1, is a three-dimensional nanomechanical computeraided design (CAD) program, including both a CAD module for the design and modelling of atomically precise components and assemblies and a molecular-dynamics module for setting up and simulating mechanical nanodevices. NanoRex has scheduled the product for release in 2006.
In Singapore to deliver a talk on engineering from the bottom up, Drexler paints a broad scenario of atomically precise nanotechnology in such fields as chemistry, biotechnology, semiconductor surfaces, and nanotubes. Those technologies will come together in an engineering framework to build atomically precise functional nanosystems in a wide range of applications -- energy, medicine, and instrumentation, and so on.
He sees the key strategic objective is to build mechanisms that can themselves be tools for building additional atomically precise systems (like the ribosomes in living cells that synthesise proteins). In terms of applications along this pathway, researchers already produce a wide range of useful atomically precise systems. He is convinced that continuing to focus on integrating these technologies will be fruitful.
When will actual systems become reality? Drexler stresses instead, "The question should be: when will we see the development of systems of that broad class that make innovative building blocks with a new kind of usefulness?"
In less than a decade, he believes, the world can achieve a useful second-generation productive nanosystem, something he calls a "Mark II" ribosome. When it will happen depends on funding and interested parties' willingness to take a collaborative engineering approach to system building.
He cites a productive nanosystem developed by Nadrian Seeman, a New York University researcher. A tiny device made of DNA fragments takes information from DNA and uses it to direct the assembly of other building blocks also made of DNA. The discovery demonstrates that the principle of artificially directed assembly may not be distant.
Into what areas would these productive systems fall? One would be instrumentation; a possible system is a 10nm device that reads DNA at 1,000 bases per second. It would comprise a molecular sensor and an exonuclease (an enzyme that catalyses the removal of single nucleotides from the end of a DNA chain) on an electronic substrate; it reads digital data from the DNA and outputs the information in a form readable by computer. Reading the same sequences repeatedly enables errors to be corrected. Such devices may lead to the sequencing of a patient's genome in an afternoon.
What can we expect from a nanotechnology reality check? Drexler senses a conscious effort on the part of the research community and industry to define the growth or potential of productive nanosystems. He feels that the US has been more reluctant than the rest of the world to solidify this objective. Now participants -- including companies managing billions of dollars in research tightly connected to laboratories, industry, and academia from such top-ranking research institutions as Harvard, University of California at Berkeley, and California Institute of Technology -- are collectively charting a path integrating these atomically precise technologies and climbing the ladder of productive nanosystem technology. This positive move changes the landscape; people have renewed understanding of the larger longer-term potential.
Drexler thinks Asia has the opportunity to lead in the nanotechnology game as it presents a level field with a distant horizon leading to more strategic objectives. Even though many directions taken will not lead to immediate payoff, each represents a step towards important objectives.
He sees another major differentiator for Asia in its manufacturing prowess: "Productive nanosystems refer to capabilities that emerge downstream. As we climb the rungs of the ladder of productive nanosystems, there are prospects for large-scale production of atomically precise products with high productivity and low cost. No other concept proposed is competitive or can accomplish similar goals.
"Down the path, the products of productive nanosystems will fit into conventional manufacturing processes -- components for new materials, instruments, and digital systems. Molecular components are now on the recently released international technology roadmap for semiconductors. Work on productive nanosystems will bring together research from across the many fields of nanotechnology. Almost all areas can contribute components and techniques to the engineering of productive nanosystems, and almost all areas can benefit from the new nanoscale building blocks that productive nanosystems will make." He foresees the introduction of new processes for making things that serve human needs like energy, display, transportation, medicine, and a broad range of technologies superior in performance and cost.
What catalysts can speed up the realisation of productive nanosystems?
Drexler notes: "In science and technology, many advances build upon one another; you learn things that lead to your using existing tools and materials to try something else or to combine them to further knowledge. These advances are like the trunk of the tree of advancing technologies -- applications are the fruitful branches."
He predicts: "The awareness that a technology trunk in nanotechnology exists, in which each step directly and powerfully enables the next, will catalyse development. That realisation and the understanding that the output downstream will unfold in improvements in key technological parameters will lead far-sighted nations to focus and move forward."
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